The biggest temperature swing occurs between September and October, with a change of 5.9°C / 42.6°F.
| Month | Low Temperature | High Temperature | Category |
|---|---|---|---|
| January | 1.8°C | 7.3°C | COLD |
| February | 1.5°C | 8.3°C | COOL |
| March | 3°C | 10.5°C | COOL |
| April | 4.8°C | 13.3°C | COOL |
| May | 8.2°C | 16.9°C | MILD |
| June | 11.1°C | 19.8°C | MILD |
| July | 13.7°C | 23.9°C | WARM |
| August | 14°C | 23.9°C | WARM |
| September | 11.6°C | 20.4°C | MILD |
| October | 7.7°C | 14.5°C | COOL |
| November | 4.1°C | 9.7°C | COOL |
| December | 1.8°C | 6.7°C | COLD |
November is wettest at 195.9 mm / 7.71 inches, while July is driest at 21.5 mm / 0.85 inches.
| Month | Baseline | Rainfall | Category |
|---|---|---|---|
| January | 0 mm | 178.4 mm | WET |
| February | 0 mm | 119 mm | MODERATE |
| March | 0 mm | 133.8 mm | WET |
| April | 0 mm | 98.5 mm | MODERATE |
| May | 0 mm | 73.5 mm | MODERATE |
| June | 0 mm | 56.5 mm | LIGHT |
| July | 0 mm | 21.5 mm | LIGHT |
| August | 0 mm | 32.9 mm | LIGHT |
| September | 0 mm | 65.1 mm | MODERATE |
| October | 0 mm | 131.9 mm | WET |
| November | 0 mm | 195.9 mm | WET |
| December | 0 mm | 182.5 mm | WET |
June has the strongest UV (about index 7.6), rated high.
| Month | Baseline | UV Index | Category |
|---|---|---|---|
| January | 0 | 2.3 | LOW-MOD |
| February | 0 | 3.6 | MODERATE |
| March | 0 | 5.2 | MODERATE |
| April | 0 | 6.7 | HIGH |
| May | 0 | 7.4 | HIGH |
| June | 0 | 7.6 | HIGH |
| July | 0 | 7.6 | HIGH |
| August | 0 | 7.1 | HIGH |
| September | 0 | 5.9 | MODERATE |
| October | 0 | 4.4 | MODERATE |
| November | 0 | 2.7 | LOW-MOD |
| December | 0 | 1.7 | LOW-MOD |
Daylight ranges from 8.5h in December to 15.9h in June, a 7.4h difference.
| Month | Baseline | Daylight Hours | Category |
|---|---|---|---|
| January | 0h | 8.9h | SHORT |
| February | 0h | 10.3h | BALANCED |
| March | 0h | 11.9h | BALANCED |
| April | 0h | 13.7h | LONG |
| May | 0h | 15.2h | LONG |
| June | 0h | 15.9h | LONG |
| July | 0h | 15.5h | LONG |
| August | 0h | 14.2h | LONG |
| September | 0h | 12.5h | BALANCED |
| October | 0h | 10.8h | BALANCED |
| November | 0h | 9.3h | SHORT |
| December | 0h | 8.5h | SHORT |
Daylight varies from 8.5 hours in December (winter) to 15.9 hours in June (summer), which is a difference of 7.4 hours.
Northern Hemisphere seasons shape the weather patterns throughout the year. Here's what to expect in each season:
Click any month for detailed weather information and packing advice.
Get personalized month rankings based on weather comfort, outdoor activity suitability, and seasonal conditions.
View Best Time to VisitThe best months to visit Seattle depend on your preferences. For warm weather, August is typically the warmest month. For dry conditions, July, August, June tend to have the least rainfall. Consider your priorities, and whether you prefer warmer temperatures, drier weather, or longer daylight hours.
August is typically the warmest month in Seattle, with average high temperatures reaching around 24°C (75°F). This is peak summer weather, ideal for outdoor activities and sightseeing.
February is usually the coldest month, with average low temperatures dropping to around 2°C (36°F). Pack warm layers if visiting during this time, especially for evening activities.
November typically sees the most rainfall in Seattle, averaging around 196mm (7.7 inches). It's wise to pack waterproof layers and have some indoor backup plans if you're visiting during this month.
July is typically the driest month, with average rainfall of just 22mm (0.9 inches). This makes it an excellent time for outdoor exploration and activities with minimal risk of rain disruption.
Temperatures in Seattle range from average lows of 7°C (45°F) to highs of 15°C (58°F). This variation means you'll want to pack differently depending on when you visit, as layers are key for adapting to the seasonal changes.
Yes, sun protection is important in Seattle. UV levels can reach 8 during peak months, which is considered high. Pack sunscreen (SPF 30+), sunglasses, and a hat, especially if you'll be outdoors for extended periods.